The present invention relates to an improved air bag for a passenger safety system and more particularly to an air bag formed of a single piece of material and method of fabricating same.
Air bags or cushions have been proposed for use in passenger safety restraint systems for automotive vehicles. The type of air bag used to protect the driver typically has a generally circular balloon type shape when inflated. This bag, formed of two connecting pieces, is relatively small since its primary purpose is to protect only the driver. The passenger side air bag is typically used to protect the outboard seated passenger and, if applicable, the middle seated passenger. A passenger side air bag or cushion presents a relatively large frontal area to protect these passengers, and it has a relatively complicated shape. FIG. 1 is illustrative of a prior art passenger side air bag fabricated from a main panel 20, having a narrowed neck portion 22 and two isoconic (kidney) shaped side panels 26 (only one of which is shown). Each side panel includes a narrowed neck portion 28. The main panel 20 is stitched about a long, arcuate seam 24 to each side panel 26. The main panel forms a top 30, front 32, and bottom 34 of this type of air bag. The significance of the dotted line 150 is discussed below.
The attachment of the main panel 20 to the two side panels 26 is accomplished by sewing along the seam 24. If sewing is done manually, the procedure is cumbersome and complicated due to the length and curved nature of the seams. It has been proposed that the sewing be performed in an automated manner which could require use of three-dimensional sewing machines utilizing at least three axis movements (X,Y,Z). The capital investment in this type of machine is very costly and the process of sewing utilizing these three-dimensional sewing machines is relatively complicated.
The present invention provides an air bag or cushion fabricated of a single piece of material. The material is configured in a manner such that the resulting sewing operations are along straight or slightly curved stitch or sewing patterns. These stitch or sewing patterns when sewn will define the shape of the bag and can be performed utilizing standard sewing machines avoiding the necessity of utilizing the more costly three-dimensional sewing machine.
It is an object of the present invention to provide an air bag that is simple to manufacture and one that can be fabricated from a single piece of material. Another object of the present invention is to provide an air bag which utilizes a minimum amount of material.
Accordingly, the present invention comprises: an air bag formed of a single piece of material having a plurality of triangular portions extending outwardly from a main section of material. The edges of adjacent triangles are joined together such as by sewing to form parts of the side panels of the air bag. More specifically, the preferred embodiment of the air bag comprises: a generally oblong piece of material suitable for use as an air bag or cushion including: first and second ends, and first and second sides opposingly situated when the material is laid flat. The first side includes a plurality of adjacent first triangular-like shapes and the second side includes another plurality of adjacent second triangular-like shapes. Each side includes a transition edge extending from a respective end to an edge of certain triangular-like shapes. Adjacent edges of the various triangular-like shapes and certain pairs of the transition edges are sewn together to form the material into the desired shape of an air bag.
Many other objects and purposes of the invention will be clear from the following detailed description of the drawings.